Labels and other similar tags have long been used to identify, for instance, the manufacturer, fabric type, cleaning instructions, and sizes of various products, including clothing. As manufacturing and efficiency requirements have continued to increase, programmable sewing machines began being utilized to perform certain repetitive portions of the manufacturing process, including label sewing operations. Programmable sewing machines are useful for these types of purposes since numerous sewing patterns may be stored in computer memory and subsequently accessed by an operator to produce a desired design on the given material(s), namely by moving the material(s) relative to the sewing needle with an arch clamp assembly and attached clamping devices which appropriately engage the material(s). Consequently, a sewing pattern which follows the contour of a given label may be stored in computer memory and accessed by the operator after having appropriately positioned the label upon the product. When the program is initiated, the programmable sewing machine sews the desired pattern to appropriately attach the label to the product.
Various clamping devices have been used with arch clamp assemblies to perform the label sewing operations, including square- or rectangularly-shaped clamps having an open interior ("open square clamps"). An upper and lower open square clamp of the described configuration are attached to the arch clamp assembly to engage the product and label therebetween. Once a sewing pattern is entered into the computer memory of the programmable sewing machine which directs the sewing needle to move, relatively, around the interior of the open square clamps to attach the label to the given product, repetitive label sewing operations are achievable.
Although open square clamps utilize the inherent capabilities of the programmable sewing machine, namely its ability to perform repetitive functions in an automated manner, such clamps have a number of existing deficiencies. For instance, the label or tag is only held along its edges by the open square clamps and thus there is a tendency for the label to pull away from between the clamps. This problem is magnified when thin labels are being used. Relatedly, the sewing needle is unable to get very close to the edge of the label since the open square clamps must be able to engage a sufficient amount of the label to avoid the problem of the label pulling out from between the clamps. Consequently, unsecured portions of the label (i.e., those exterior of the sewing pattern) may irritate the user of the product, particularly if the product is an article of clothing. Moreover, since the label is only held along its edges, there is a tendency for the label to "pucker" to a certain degree which is not only aesthetically displeasing, but which may be quite uncomfortable if the label is affixed to an article of clothing. This particular problem is magnified when the label is being sewn onto a product which contains a filler material (i.e., a down-filled jacket), since when the open square clamps are engaged, the filler material tends to bulge up into the open, interior portions thereof.
In recognition of the deficiencies of open square clamps, an alternative was developed for use with programmable sewing machines which firmly secures substantially the entire label against the product. Generally, the alternative clamping device includes an outer, open interior clamping device similar to that described above (i.e., an upper and a lower clamp of the described configuration, but of a larger inner area) which is attached to the arch clamp assembly to engage and move the product relative to the sewing needle to produce the desired pattern thereon. In addition, a solid, appropriately configured clamping plate (i.e., one which follows the contour of the label) is positioned on the interior of the outer clamps and is connected to the arch clamp assembly to firmly secure substantially the entire label down upon the product before sewing operations are initiated. Only a limited amount of the label is exposed so that a sewing pattern may be positioned thereon. Consequently, a sewing pattern is stored in the machine's computer memory which follows the contour of the clamping plate to effectively attach a label around the entire perimeter thereof to a given product.
Although the clamping plate configuration reduces or eliminates puckering of the label and the potential for the label pulling away from the clamping device during operation, a problem existed regarding its connection to the arch clamp assembly. More particularly, a connector had to be developed which would allow the sewing needle to "travel" around the entire perimeter of the clamping plate and label or else the label would not be attached to the product over a defined area. The resultant connector was an invertible, substantially U-shaped connector having a cavity with a single opening thereto. This connector can assume a position such that the sewing needle may be within the cavity and exit through the opening thereto when label sewing operations are initiated. As the sewing needle "travels" around the label and clamping plate and nears completion of the 360.degree. pattern therearound, the connector is inverted such that the sewing needle may again pass through the opening and enter the cavity of the connector to complete the desired full 360.degree. pattern. Thereafter, the sewing needle is raised above the label and product and the threads are cut to terminate the sewing pattern. Furthermore, the connector is inverted back to its original position for subsequent operations and the sewing needle may assume its original position.
Although the U-shaped, invertible connector allows for 360.degree. label sewing operations, the problem with past and existing systems utilizing this device is that a drive assembly (e.g., motor and gear configurations, hydraulic systems, pneumatic systems, solenoids) is incorporated into the programmable sewing machine to actually drive the U-shaped connector between its two described positions. There are a number of deficiencies associated with these driven U-shaped connectors. For instance, the material costs are naturally increased since a separate drive assembly must be installed with the programmable sewing machine. Relatedly, maintenance costs are also increased since there are more components to the label sewing apparatus, and particularly since the U-shaped connector is susceptible to breakage based upon the force which is typically maintained thereon by the drive assembly throughout the entire label sewing operation. Furthermore, in order to take advantage of the capabilities of the programmable sewing machine, i.e., its ability to perform repetitive functions in an automated manner, it is necessary to incorporate the drive assembly within the programmable sewing machine's computer software. Consequently, not only is the drive assembly itself cumbersome and expensive to install, but this required modification of the software is also time consuming and thus expensive. As a result, these systems are usually installed by a field technician versus the owner of the programmable sewing machine and thus are more likely to be designated for this single function due to the typical conversion costs.
Based upon the foregoing, there is a need for a label sewing apparatus which will firmly secure substantially the entire label down upon the product to reduce or eliminate puckering. Furthermore, there is a need for a label sewing apparatus which may be installed on a programmable sewing machine without requiring the assistance of a trained technician, but which still allows the sewing needle to travel the full 360.degree. around the label. Relatedly, there is a need for such a device which does not need a separate drive assembly which must be incorporated into the software of the programmable sewing machine, thereby avoiding increased installation and subsequent maintenance costs.